JPS62263137A - Polyphenol compound and production thereof - Google Patents

Abstract

NEW MATERIAL:A polyphenol compound of formula (X is bivalent group of formula II or III; R is H or 4-hydroxy-3,5-dimethylphenylmethyl; n is 0 or integer of 1-3). EXAMPLE:Hexaphenol of formula IV. USE:An intermediate raw material for polyepoxy resin capable of giving a cured product having excellent glass transition temperature, heat-distortion temperature, high-temperature elasticity, etc. PREPARATION:The polyphenol compound of formula I can be produced by reacting polymethylol bisphenol A of formula V (A is H or methylol) with at least equivalent of 2,6-xylenol based on the methylol group of the former compound.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a polyphenol compound having a novel structure and a method for producing the same. More specifically, the present invention provides a novel polyphenol compound useful as an intermediate raw material for polyepoxy resin that can provide a hard material with excellent heat resistance properties such as glass transition temperature, heat distortion temperature, and custom heat-resistant elasticity, and a method for producing the same. It is related to.

Conventional technology Traditionally, epoxy resin has limited mechanical and electrical properties.

Adhesion, heat resistance, etc. kg! Because of this, it is widely used in adhesives, paints, encapsulants for electronic components, and matrix resins for carbon fiber-reinforced plastics. In the fields of electronic parts encapsulants, advanced composite materials (ACM), etc., there is a demand for epoxy resin-curable compositions that have excellent heat resistance properties such as glass transition temperature, heat distortion temperature, and heat-resistant elastic properties. There is.

Up to now, examples of the polyepoxy compounds constituting the epoxy resin curable composition with excellent heat resistance: P- include epoxidized phenol novolak resin@, epoxidized 0-cresol novolak resin, 1.1, 2.2- Polyglycidyl ethers of polynuclear phenols such as tetraglycidyl ether of tetrakis(p-hydroxyphenyl)ethane, tetraglycidyl compounds of xylylene diamine,
Polyglycidylated aromatic polyamines such as triglycidylated incyanur are widely used. However, the epoxy resin curable compositions used with these polyepoxy compounds do not have the above-mentioned heat resistance properties.
However, there is a need for the development of epoxy resins with even better heat resistance.

By the way, recently it has been obtained by the reaction of tetramethylolbisphenol A and phenol or 0-cresol. A hexaglycidyl ether of a polyphenol represented by the general formula (wherein B is a hydrogen atom or a methyl group) has been proposed.
(Special Publication No. 1983-500024).

However, the polyphenol represented by the general formula 〇) has low thermal stability and is easily made to have a high molecular weight by heat treatment, so various difficulties arise when producing this polyphenol. In some cases, a step is required to remove unreacted phenol or 0-cresol from the reaction product, and unreacted phenol or 0-cresol is usually removed by vacuum distillation or steam distillation, but this 1 requires raising the temperature to 150-180°C. However, at such high temperatures, polyphenols tend to polymerize, their melt viscosity increases, fluidity decreases, and they turn black, and they also contain methylene ether groups (-CH20CH2-). Compounds with this will be mixed in as by-products. Generally, this methylene ether group is thermally unstable, and if it exists in a polyepoxy compound, it will significantly reduce the heat resistance of the cured product.
However, it is necessary to convert it into a thermally stable methylene group (-CH2-) by heat treatment at a temperature of ℃ or higher.

A temperature of 170° C. or higher is accompanied by an increase in the molecular weight of the polyphenol. Polyphenols with high molecular weight in this way cause problems such as the epoxidation reaction with shrimp halohydrin progressing extremely slowly and the softening point of the obtained polyepoxy compound becoming extremely high, making it impractical for practical use. cannot be used.

However, in the production of the polyphenol represented by general formula (1), if the molar ratio of the phenolic hydroxyl group of phenol or 〇-cresol to the methylol group of the raw material tetramethylolbisphenol A is 2 or less, the oligomer is mainly The desired polyphenol represented by the general formula (+) is produced in only a small amount (Japanese Patent Publication No. 1983).
-500024).

Therefore, to obtain highly pure polyphenols,
It is necessary to have a very high molar ratio of phenolic hydroxyl groups/methylol groups of 8 or more, which requires a large amount of phenol or o-cresol to be removed and recovered from the reaction product, resulting in increased costs. There is no excuse for being economically disadvantaged.

In this way, the polyphenol represented by the general formula CI) overcomes the drawback of low thermal stability, and the curable composition of the polyepoxy compound obtained from it also has sufficient heat resistance properties. However, there is a need for the development of an epoxy resin with even better heat resistance.

Problems to be Solved by the Invention Under these circumstances, the purpose of the present invention is to improve heat resistance properties such as glass transition temperature, heat distortion temperature, and heat elasticity properties, and to provide a cured product compared to conventional ones. The object of the present invention is to provide a polyphenol compound suitable as an intermediate raw material for producing a polyepoxy compound.

Means for Solving the Problems The present inventors have conducted intensive research to develop an intermediate raw material for a new polyepoxy compound exhibiting the above-mentioned desirable properties of O. As a result, we have found that polymethylolbisphenol A and the methylol group therein It has been found that the object can be achieved by reacting 2,6-xylenol with at least an equivalent amount of 2,6-xylenol.

Based on this knowledge, we have completed the present invention.

That is, the present invention is based on the general formula (wherein X is a divalent group represented by or, R is a hydrogen atom or 4-hydroxy-3,5-dimethylphenylmethyl L, The present invention provides a polyphenol compound represented by: This product includes, for example, polymethylolbisphenol A represented by the general formula (A in the formula is a hydrogen atom or a methylol group) and 2,6-xylenol in an amount of at least equivalent to the methylol group in the acidic catalyst. It is obtained by reacting in the presence of

Polymethylol bisphenol A represented by the general formula CI can be obtained by reacting bisphenol A with 4.0 to 4.4 moles of formaldehyde per mole thereof in the presence of a sodium hydroxide catalyst, for example. Can be done. This reaction product usually contains 80% or more of tetramethylolbisphenol A, trimethylolbisphenol A, and the like.

By reacting the polymethylol bisphenol represented by the general formula ([I) obtained in this way with 2,6-xylenol in an amount equivalent to or more than the methylol group in the presence of an acidic catalyst, A polyphenol represented by the general formula (n) is obtained. The molar ratio of 2,6-xylenol to methylol group is usually 1.0 to 10%.
It is preferably selected within the range of 1.2 to 5. When this molar ratio is less than 1.0, the reaction product tends to contain a large amount of self-condensed product of polymethylolbisphenol A, and when it exceeds 10, excess 2,6-xylenol is removed from the reaction product. This is not preferable because the cost of recovery increases.

The acidic catalyst used in this reaction is:

Examples include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, and organic acids such as oxalic acid and succinic acid.

The amount of these catalysts to be used is usually selected within the range of 0.02 to 2 weight ratios based on the total i it K of polymethylolbisphenol A and 2,6-xylenol.

In addition, the reaction temperature is usually 50 to 120" C1, preferably 7
The temperature range is 0 to 105°C.

In this reaction 5 of polymethylolbisphenol A and 2,6-xylenol, a hexaphenol compound represented by the structural formula is produced as a main component, and various other oligomers are also produced.

Examples of this oligomer include the following dimers and trimers.

Regarding the formation mechanism of this oligomer, for example, the condensation reaction of tetramethylolbisphenol A and trimethylolbisphenol A produces an intermediate represented by the structural formula (%), and 2,6-xylenol is added to this intermediate. It is thought that the above-mentioned dimer is produced by the reaction. A similar production mechanism can be considered for trimer or higher oligomers. Trimethylol bisphenol A and 2
, 6-xylenol produces polyphenol compounds with the following structural formula.

In order to selectively convert the dimer into hydrogen, first, in the methylolation reaction of bisphenol A, bisphenol A
A mixture of approximately equivalent amounts of trimethylolbisphenol A and tetramethylolbisphenol A is produced by reacting 3.5 moles of formaldehyde per mole. Next, by reacting this methylolated product with 2,6-xylenol under acidic conditions, a dimer can be selectively produced using the oligomer formation mechanism described above.

For the trimer, 1 mole of bisphenol A is reacted with 3.0 moles of formaldehyde to dimethylol bisphenol A, )l in a methylolation reaction.
/A mixture of approximately equivalent amounts of methylolbisphenol A and tetramethylolbisphenol A is prepared. Next, by subjecting this methylolated mixture to a 2,6-xylenol reaction under acidic conditions, polyphenols containing trimers and dimers as main components can be produced.

About 70% of the polyphenol represented by the general formula (■) obtained by such a reaction is a hexaphenol compound represented by the above formula □□□, and about 30% is an oligomer.

In the production of the polyphenol represented by the general formula (It), since the reaction is carried out with an acidic catalyst as described above, the condensation reaction between the methylol groups in different molecules of polymethylolbisphenol A is Since the reaction rate is higher than that of the condensation reaction between 2,6-xylenol and the ring hydrogen, it is impossible to reduce the amount of oligomer produced to substantially zero, but the condensation reaction between the methylol groups is as much as possible. In order to suppress the reaction, it is advantageous to use a method in which polymethylolbisphenol A is added dropwise into 2.6-+talenol present in excess under an acidic catalyst.

In this way, polymethylol bisphenol A and 2
．． The reaction solution obtained by reacting with 6-xylenol contains excess 2,6-xylenol and a catalyst in addition to the polyphenol represented by the product general formula (n). After the reaction solution is extracted with water to remove the catalyst, it is desirable to remove the 2,6-xylenol using a vacuum evaporator or the like. Removal of 2.6-xylenol is usually carried out at a temperature of 150-160°C. Furthermore, methylene ether bonds (-C
In order to decompose the compound having H20CH2-) and convert it into a stable methylene bond (-CH2-), it is preferable to heat-treat one reaction product at a temperature of usually 180 DEG C. for about one hour.

Since the polyphenol represented by the general formula (II) has excellent thermal stability, it is hardly recognized that the polyphenol has a high molecular weight by the above-described heat treatment operation. The cause of this thermal stability is thought to be due to its chemical structure. That is, the main component of the polyphenol represented by general formula (II) is a hexaphenol compound represented by Since the groups are bonded, there is no reactive active site, and therefore, it is thought that the reaction between the compounds does not proceed and the molecular weight does not increase due to the heat treatment operation.

In contrast, polyphenols represented by the general formula (1) % formula % (E in the formula is a hydrogen atom or a methyl group) (Japanese Patent Publication No. 1983-500024) have a phenolic hydroxyl group. , at least one of the 2 and 6 positions has no substituent bonded, so an active site exists,
It is thought that some kind of reaction occurs in the polyphenol due to the heat treatment operation, resulting in a higher molecular weight.

The polyphenol represented by the general formula C11) of the present invention is.

By reacting with epihalohydrin by a known method, a polyepoxy compound represented by the general formula (V) or (where 2 is a hydrogen atom or ) can be obtained.

This polyepoxy compound produced from the polyphenol compound of the present invention can be used as an epoxy resin curable composition by blending it with a curing agent. As the curing agent blended into this epoxy resin curable composition, any compound can be used from among the compounds conventionally known as curing agents for epoxy resins.

Effects of the Invention The polyepoxy compound produced from the polyphenol compound of the present invention has particularly excellent heat resistance properties such as glass transition temperature, heat distortion temperature, and heat-resistant elastic properties, as well as mechanical properties such as 1 bending strength and isot impact strength. It can provide cured products with excellent properties, such as adhesives, stickers, paints, insulating materials, laminates, laminates for printed circuits, or sealing materials for transistors, ICs, LSIs, switches, and connectors. It is suitable for use in molding materials such as. Note that the novel polyphenol compound of the present invention is also used as a curing agent for epoxy resin.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these examples in any way.

Example 1 Bisphenol A 228 F (1.0 mol) t-
Pour 200 ethanol into a 21' glass flask.
,Wednesday 520? , add caustic soda 809 (2.0 mol), stir at 60°C for 30 minutes, cool to room temperature, and add 328 r (4.05 mol) of a 37% formalin aqueous solution.
When the mixture was stirred at 50°C for 5 hours, a yellow transparent viscous liquid was obtained. The residual formaldehyde in this reaction solution was 0.30% (formaldehyde reaction rate 96.7%).
) Adashi, the results of analysis by liquid chromatography,
Tetramethylol bisphenol A was 82% and trimethylol bisphenol A was 17%. Raw material bisphenol A was not detected.

Production of polyphenol 2,6-xylenol 976 in a 3 ton glass flask
P (8.0 mol) and 36% hydrochloric acid 1 as a catalyst.
After adding 49, the reaction solution of polymethylol phenol A was neutralized with 36% hydrochloric acid and the solution was heated to the reaction temperature f.
: While maintaining the temperature at 80°C, it was dropped into the flask over 2 hours, and the mixture was further stirred at 80°C for 5 hours. Next, the reaction solution was cooled to room temperature and allowed to stand, then the upper aqueous layer was removed, the organic layer was washed three times with water 1000*, and then the solvent and 2.6 - removed xylenol. Further, in order to completely remove the methylene ether bonds, heat treatment was performed at 180° C. for 1 hour, and polyphenol 6959 (91% of the theoretical value for hexaphenol) was obtained as a yellow transparent solid.

As a result of analysis by gel permeation chromatography, the composition of this polyphenol was found to be 70% hexaphenol compound represented by structural formula (IV), 27% olicomer,
Bis(4-hydroxy-3,5-dimethylphenyl)
Methane was 3%.

As a result of dissolving this polyphenol in chloroform-61 using VC and measuring IH and 13C nuclear magnetic resonance spectra, it was confirmed that a compound having the following structural formula was the main component.

Polyphenol 300f (
After adding and dissolving shrimp chlorohydrin 1527 f (16.5 mol) and methyl cellosolve 4502, the temperature was raised to 60°C, and the temperature was raised to 60°C. , 358 mol) was added dropwise into the flask at a constant flow rate over 3.5 hours. After cooling the reaction solution, the precipitated common salt was filtered out,
Excess epichlorohydrin, methyl cellosolve, and water in the filtrate were removed by evaporation at 80 to 90°C using a vacuum evaporator. Next, 1500 f'fH of methyl inbutyl ketone was added to the obtained solid to dissolve it, and then 75 o2 of water was added to this solution and shaken to extract and remove the remaining common salt. This extraction operation was repeated three times. The obtained organic layer was heated to 140 to 15 degrees using a vacuum evaporator.
Removal of the solvent at 0'C gave polyepoxy compound 4282 as a clear pale yellow solid (99% of theory for hexaglycidyl ether).

This one is IH and 13G nuclear magnetic resonance Subek)/I/
As a result of structural analysis by and gel permeation chromatography, it was confirmed that hexaglycidyl ether having the following structural formula was the main component.

CH2-CHCH2OCH5CH50-a(2-CH-
CH2\0'\0/Again.

The epoxy equivalent according to the CTAB method (cetyltrimethylammonium bromide method) was 198.

Incidentally, FIG. 1 is a gel permeation chromatography (GPC) chart of the polyphenol. In the calibration curve using phenol novolac resin, the retention capacity was 20 ntl.
has a molecular weight of about 2000.227! has a molecular weight of about 1000
．． 24- had a molecular weight of about 500.

The peak of retention capacity 23- in Figure 1 is a hexaphenol compound (molecular weight 764) represented by the structural formula (product).
It is clear that

FIG. 2 is a GPC chart of the polyepoxy compound. In the following calibration curve using epoxy cresol novolac resin, retention capacity 20-go had a molecular weight of about 2,500, 22- had a molecular weight of about 1,500, and 24- had a molecular weight of about SOO.

The peak of retention capacity 23- in FIG. 2 corresponds to the structural formula (I
It is an epoxidized product (molecular weight 1178) of a hexaphenol compound represented by V), and the peak with a retention capacity of 18 to 22- is an epoxidized product integrated with an oligomer.

Figure 3 shows a CD containing 1:% TM5t of the polyphenol.
Dissolved in Cl3, JASCO Corporation GX-270 type FT-N
Proton-nuclear magnetic resonance (I H-NMR) using MR
) The attribution of the signals in the spectrum diagram is as follows.

Chemical shift Attribution 1.4-1.7 ppm: Hydrogen of methyl group derived from bisphenol A 1.8-2.2 ppm: Hydrogen of methylene group resulting from hydrogenation of methyl group derived from 2.6-xylenol 4.7-4.9 ppm: Hydrogen of phenolic hydroxyl group 6.6-7.2 ppm: Hydrogen directly connected to aromatic ring Also, according to the intensity ratio of each signal in this figure, this polyphenol It is clear that approximately 3.5 molecules of 2,6-xylenol and approximately 3.5 equivalents of methylene groups are bound per molecule of bisphenol A, and this result is in good agreement with the GPC chart in Figure 1. The polyphenol content is approximately 70% of Nanatsuma Ichigo and approximately 30% of the polyphenol content.
It is shown that it contains an oligomer of .

Figure 4 shows one of the polyphenols produced by the same model as above.
30-NMR spectrum, and the attribution of the signal of fn is as follows.

Chemical shift Attribution: 16 ppm 42.0 ppm of carbon in methylene group bonded to methyl group derived from 2,6-xylenol: 123 to 151 ppm of quaternary carbon derived from bisphenol A: Carbon forming aromatic ring In the case of 13C-NMR, the signal intensity ratio is not necessarily the same as the presence of each n carbon.

Figure 5 shows the polyepoxy compound containing 1% TMS.
It is a 'fcIH-NMR spectrum measured after dissolving in Dct5.

Comparing with Figure 3, the hydrogen signal of the hydroxyl group that existed at 4.7 to 4.9 ppm has disappeared, and 2 new signals have been added.
．． Complex signals of three types of hydrogen in the glycidyl group appear at 4 to 4.2 ppm.

FIG. 6 is a 130-NMR spectrum of the polyepoxy compound.

Compared to Figure 4, it is 44.5 ppm, so, s pp
Three types of carbon signals of glycidyl groups newly appeared at 73 to 74 ppm.

Further, the GPC chart If after heat treatment at 180° C. for 5 hours is shown in FIG. 7. From FIG. 1 and FIG. 7, it can be seen that there is almost no change between before and after heat treatment.

Figure 10 shows the G of a compound presumed to be a hexaphenol compound with the following structural formula obtained by separating the λ polyphenol compound produced in Example I by thin layer chromatography.
This is a PO chart. The holding capacity in Figure 10 is 237! It is clear that the peak is the hexaphenol of the present invention (molecular weight 764).

Figure 11 shows the above hexaphenol compound in CDCl3.
proton-nuclear magnetic resonance (IH-NMR) dissolved in
) is a spectrum.

The attribution of each signal is as follows.

Chemical shift Attributable hydrogen: 4.8 to 4.9 ppm: Hydrogen of phenolic water group: 6.7 to 7.2 ppm: Hydrogen directly connected to the aromatic ring. Based on the intensity ratio, this compound has about 40% of bisphenol AI molecules.
It is clear that about 4 molecules of methylene groups are bonded to the 2,6-xylenol molecule. From this result and the GPC chart shown in FIG. 10, it was confirmed that this compound is the hexaphenol compound of the present invention.

Examples 2 to 5 Polyphenols and polyepoxy compounds were synthesized by the same operations as in Example 1 under the conditions shown in Table 1.

Comparative example In the development of polyphenols in Example 1.

A polyphenol containing a hexaphenol compound having the following structural formula as a main component was obtained in the same manner as in Example 1 except that phenol was used in place of 2.6-xylenol.

Further, in the same manner as in Example 1, it was reacted with shrimp chlorohydrin to obtain an epoxy resin.

FIG. 8 is a GPC chart of the polyphenol,
FIG. 9 is a GPC chart after the polyphenol was heat-treated at 180° C. for 5 hours. From Figure 9, holding capacity 2
It can be seen that the amount of monomers present in 4G has decreased and the amount of high molecular weight materials has increased.

Application Examples Epoxy resins obtained in Example 1 and Comparative Example 1, and epoxy cresol novolak resin (ECN-273).

(manufactured by Asahi Kasei ■) under the curing agent, compounding composition, and curing conditions shown in Table 2, and the physical properties of the resulting cured product were measured. The results are shown in Table 3.

Table 2 Note 1) DAP Metaphenylenediamine 2) D
DM Diaminodiphenylmethane 8) Equivalent/Epoxy Equivalent Figure 3

[Brief explanation of drawings]

1, 3 and 4 are GPC charts of the polyphenols obtained in Example 1. The I H-NMR spectrum diagram, the 13C-NMR spectrum diagram, FIGS. 2, 5, and 6 are those of Example 1, respectively.
A GPC chart of the polyepoxy compound obtained in . IH-NMR spectrum and 1"C-NMR spectrum, Figure 8 shows the Gp of the polyphenol obtained in the comparative example.
This is an e-chart. Figures 7 and 9 show the concentrations of the purified polyphenol obtained in Example 1 and the polyphenol obtained in Comparative Example, respectively.
'c% It is a GPC chart after heat treatment for 5 hours. FIG. 10 and FIG. 11 are GPC and 'H-NMR spectra of hexaphenol obtained by separating it from the polyphenol obtained in Example 1, respectively.

Claims (1)

[Claims] 1 General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (X in the formula is represented by ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ OH or HO ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ R is a hydrogen atom or a 4-hydroxy-3,5-dimethylphenylmethyl group, n is 0 or 1
An integer of ~3) A polyphenol compound represented by: 2. Claim 1, which is hexaphenol represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼
The polyphenol compound described in . 3. In the presence of an acidic catalyst, polymethylol bisphenol A represented by the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (A in the formula is a hydrogen atom or a methylol group) and the methylol group therein There is a general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (where X is ▲ ▲ there is a mathematical formula, chemical formula, table, etc. ▼ OH or HO ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Divalent group represented by R is a hydrogen atom or 4-hydroxy-3,5-dimethylphenylmethyl group, n is 0 or 1
An integer of ~3) A method for producing a polyphenol compound represented by: 4 Claim 3 in which the polyphenol compound is hexaphenol represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼
Manufacturing method described in section.